Analyzing the Monoprice Blackbird HDCP 2.2 to 1.4 Down Converter | Hacker News Reader

Analyzing the Monoprice Blackbird HDCP 2.2 to 1.4 Down Converter

tomverbeure.github.io

190 pointspicture62 comments

isn’t it funny how the entertainment industry basically stamped our piracy entirely by offering a comprehensive, more easy to use and affordable solution in the form of well-functioning online streaming, but then fucked it all up by IP cockfighting that splintered the market faster than the Weimar Republic? And if that wasn’t enough stupidity to do the trick, they force so much piracy protection up the throats of content providers til it’s unusable of a third of their clients

I wouldn't say it's funny. They had most of the stuff people wanted - easy payment monthly. Good ux. Lots of movies and tv. then they figured they could get a few more pennies than Netflix was giving and that they could do it better. Read: so far no

Netflix saw the amount of cash going out the door to studios and thought, hey we can do what they do, started shoveling their own content and overnight became the richest studio in Hollywood.

They also saw the writing on the wall when the president of HBO said that they would never license their content to Netflix. The reaction to create their own content was in response to that, among other things.

And mostly produce garbage. Netflix is definitely not forever and a huge ZIRP baby.

Seems like it's a universal law of media companies: They constantly and seemingly deliberately won't allow any distribution channel to get good enough to beat "piracy".

As soon as something comes along that has the potential of being a one-stop shop, they fuck everything up by splintering into many services you have to pay for individually.

As soon as something comes along that offers a huge catalog, they fuck everything up by fighting among themselves over IP rights and exclusivity and randomly removing random shows from random seasons.

As soon as something comes along that is cheap enough to make the risk of piracy not worth it, they fuck everything up by jacking up the price.

As soon as something comes along that delivers piracy-like video quality over streaming, they fuck it up by over-compressing it and otherwise nerfing the video quality.

It's like these media executives are meeting every year to ensure that their products are all just shitty enough to keep piracy alive.

And thats why piracy will never die.

They are trying to force a horse shit model onto consumers and a lot of technically aware consumers told them to pound sand.

Today, buying media means you are forced to watch an fbi warning that literally doesn't apply to the consumer, then the forced previews, all for a price that would be considered high, 10 years from now.

Pirate it for nothing, and not have to deal with marketing garbage forced upon you.

It's funny in a sort of sad, clown world way.

Paying customers are treated like criminals, can't download stuff to watch offline, can't even screenshot their screens without some sort of "protection" kicking in, have access to a shitty selection of titles which often lack subtitles and extra content if they aren't straight up censored or "revised", are forced to use the corporation's shitty video player software and on top of all that they get horribly compressed encodes to the point it's got artifacts in 90% black frames.

Meanwhile "pirates" get everything humanity has ever created for free in the highest quality available packaged as simple DRM-free files they can do anything they want with and that they can play on any device or with a well configured mpv.

They defeat themselves with this copyright nonsense. It gets to the point they can't match the level of service offered by a bunch of "pirates".

> Meanwhile "pirates" get everything humanity has ever created for free in the highest quality available packaged as simple DRM-free files they can do anything they want with and that they can play on any device or with a well configured mpv.

Some of the private torrent sites also serve as the most comprehensive library of any given media.

Exactly. And thats not even the full extent of the sadness. Even though i despise existing in modern academia, the broader idea of scientific curiosity as in the human trait is possibly my favorite attribute humankind has to offer. Its such an embodiment of what makes us what we are and i feel drawn to it ever since being a kid and watching space documentaries on tv with my dad.

It makes me genuinely sad that myself and pretty much everyone i know has to make use of scihub and library genesis to access the majority of our greatest achievement and culmination of unthinkable multiples of a human lifespan that went into systematically poking our enviroment and writing down its reaction.

And for what exactly? Do our contributions actually reach the ones furthering our (previously) collective knowledge, a way of financing the needed work without compromising its method? Nah. The exact opposite.

The money exclusively pays middlemen, rich enough to buy their way into a market chokehold in the first place, that contribute nothing beyond their self-made reputation mill called "prestigious journals". They gleefully allocate themselves 100% of the cake without any care in the world, consequences be damned.

Do you know what the final layer of insult looks like? After creating the very perverted system, purpose built to extract every last point of profit, after reaping the benefits available to the ones ruthless enough to be okay with making H1B slave labor their modus operandi, they come back crying to us that china stole their intellectual property.

How dare the chinese researcher, the one you forced to work themselves into burnout for half pay, treated like an indentured servant with their Visa held over their head by their mast- i mean sponsor, how dare he to head back to their home country without any feeling of loyalty towards you? Screw them. They would do and did the same and worse to us in a heartbeat.

i fortunately never have to endure this situation, but i grew up to afghan immigrant parents, so the thought of being trapped like this in a foreign country, after your entire family had to work themselves sick for your chance at a better life, all the hope and dreams you embody for your loved ones, the shame that comes with that and being confronted with loosing at all again, just because you refuse to be held as a modern day slave, jeez man.. i have tears in my eyes just thinking about it and i feel like i wanna puke. screw them.

This EZCOO HDMI splitter will also do the job as well as let you customize the EDID:

https://www.amazon.com/Splitter-l-b-y-Vision-Atmos-Scaler/dp...

Some folks use that splitter with home theater projectors to enable LLDV (player-led aka Low Latency Dolby Vision).

For more money and functionality, see the devices made by HDFury (mentioned at the end of the article). e.g. the Dr HDMI 4K:

https://hdfury.com/product/dr-hdmi-4k/

I didn't want to publicize it, just in case, to keep the supply available but now that you've done it:

I strongly recommend that product. As a STB manufacturer it is immensely useful. You can keep your 4k DV video output, and use a 10$ USB capture to develop and test as if you had a real TV.

It is also useful to reduce ewaste: there have been some 4k TVs without HDCP2. 2+HDMI 2.0, this makes it 4k again.

Likewise, I have an HDMI 1.4 AVR, this splitter allows me to use it at full feature (DTS-HD being not available in HDMI 1.4)

My only complain is not being able to switch to tunneled Dolby Vision (as a user you probably don't care), and it's not immensely stable (you probably want to give it a proper radiator)

> And that’s the end of the story: the converters work, they’re passing through type 1 contents, and there’s nothing the movie studios can do about it.

I suspect that's not giving enough credit to the lobbying industry.

Cell phones transmitting in the clear? We'll just make it illegal to sell radios to the public that can receive those frequencies!

Old TVs with "high UHF" channels could sometimes pick up early analog cell traffic. People didn't appreciate having that pointed out.

Nice to see that the classic "just lie about what you are" works fine.

As one should, when dealing with anything that interferes with your ability to use your own purchased devices.

100% agreed.

A tragic that people that are really paying for the content are blocked and have to deal with a subpar experience.

Or you pirate the show / buy a box.

I returned a very expensive monitor because HDCP failed with apps like Disney or hbo.

I work for a company that deals with SVOD/AVOD content.

It's silly how many ridiculous things the content providers try to negotiate in the contracts for their content. Some requirements they ask for are sensible (HW decryption for their high quality renditions), some are downright idiotic because they would shut out so many devices and normal users (e.g. HW decryption on audio tracks and forcing HDCP version 2.3).

We've really gone full circle and piracy is becoming the easier-to-use platform again.

Give them what they want, just make sure they pay for the support to refund 99% of people and ruin their reputation?

The thing that gets me is that normal users have no interest in bothering to pirate the content, and pirates can trivially strip HDCP with a cheap bit of kit.

Almost no copyright infringement is being prevented, only legitimate use.

Implementing and testing it all is such a pain in the ass too.

The number of people that will spend money to do this bypassing is much smaller than those that won’t. It’s like every other sort of “criminal activity”, if it’s hard to do, fewer will do it. It’s not about the consequences of getting caught that deters. It’s the level of effort required to do it.

There's not a single piracy user which has to bypass this though, they already get non encrypted files in full quality, this is only affecting legitimate purchases.

Only one person needs to actually do it, per bit of content, and seed the torrent or stick it on their friends-only warez FTP or whatever the cool kids are doing now (then someone else will make the torrent from that).

Everyone who wants to access it without paying will just get the torrent - which for some people is back to being more convenient and usable than paying for the stuff, as well as cheaper.

The only thing it really prevents is paying customers watching the thing they've rented.

And by 'just getting the torrent' they have a chance of getting a big fine. In lots of countries, there are 'anti piracy' groups trying to lobby for stupid stuff like levies on storage media (because piracy) and catching spreaders of pirated media.

They do risk that! People exceed speed limits in their cars too, with greater potential consequences. I wasn't recommending behaviour, merely describing it.

If I had to pay a "piracy tax" on equipment that may incentivise me to do some piracy. Being in the UK I'm already supposed to pay the BBC for a TV license if I watch any kind of commercial live internet stream (NHK World, Apple WWDC!) which isn't any less crazy.

Exceeding a speed limit by a few mph will not land you in jail or cost you thousands of dollars in fines in most parts of the world. Using torrents is some kind of reverse lottery: download an illegally shared movie (or for that matter: use a photo you grabbed from a random site on your own website) and get the chance to lose an annual income.

yes, let's all just do what ever we want with out respect for other people's work by grabbing their assets and using them on our websites because we have no skills to make the thing ourselves which naturally means stealing it is okay???? it never ceases to amaze me the entitlement people have. "this thing exists, so it therefore is totally reasonable for me to have it at no cost, and then make money from it without anything going back to the person that actually made it." go pound sand with that logic

Same as it always was...

It seems like deceptive advertising for Amazon to list a title for sale in a format they won't actually deliver to your device.

I just want to reiterate how fucking ridiculous it is that this thing should even exist.

Here we are almost 24 years into HDMI/HDCP and it is still trivial to make a bit perfect copy of 4K stream, and even easier to rip a 4K Blu-ray. I'd like to say the studios mostly failed, but there would be common consumer devices for copying movies, just like there used to be dual cassette tape decks for copying tapes.

I thought it was still kind of a pain to rip a 4k blu-ray?

I've only done one, but it was the same process as a regular Blu-Ray. The drive I already had was compatible.

The hard part I'm having is playback with all the bells and whistles. Afaik, support for HDR10+ output on computers is sketchy, but blu-ray menu support on playback platforms (android tv, webos, tizen, roku) is non-existant. Anyway, most devices top out at 100M ethernet, which is below the max bitrate of 4k blu-ray (peaks of 150Mbps). I've heard good things about Apple TV, but also that it's very difficult to manage unless you've got other Apple products, and my Apple IIe doesn't count.

I have a 1G Android TV device, but it still stutters in playback of high bitrate scenes when I ripped to a mkv.

I regularly play UHD HDR content I ripped from my blu-ray collection to my 4k AppleTV over 1Gbs Ethernet. I use the Infuse app instead of Plex, no stutters, no issues, looks great!

sidebar: I've had a lot of problems with the AppleTV plex app, it does not play some HDR content well, or at all. Plex on my nVidia Shield works well.

Both of my LG Blu-ray drives rip 4K discs as easily as standard 1080p discs.

My workflow is a script that calls MakeMKV's CLI with the settings I use every time. Then I run that through Handbrake to make a reasonable sized file. Just a handful of clicks.

Having a recent-ish (RTX 2070 Super) really helps as the NVenc H264/H265 engine is blazing fast (100+ fps), and is the first hardware encoder I've used that always beats Handbrake/x264 for quality and filesize.

I think I am getting confused, maybe someone can help me understand. Is the purpose of this device to allow true 4k content to be displayed on an older 4k device, i.e. one that has an older HDCP version? What was the purpose of including a 1080p TV in the test, if it could never display anything in HDR / 4k anyway, with or without the device?

> Is the purpose of this device to allow true 4k content to be displayed on an older 4k device, i.e. one that has an older HDCP version?

Yes. Or more specifically, content that the source has tagged "high value" which is often 4k.

> What was the purpose of including a 1080p TV in the test, if it could never display anything in HDR / 4k anyway, with or without the device?

From the article: > I wanted to see whether or not there’d be a visual indication that the Fire TV was playing lower quality content.

If he didn't use the 1080p TV and only had the 4K, then 1 of the following would happen:

1 black screen

2 1080p playback

3 4K playback

if he got (2), he wouldn't be able to tell if the problem was with (HDCP+4K) or just (4K). Proving that it works in 1080p on a TV that doesn't even know what 4K is establishes the baseline and eliminates the ambiguity.

Okay, that makes sense, I was definitely confused about that. Thanks for clearing that up for me.

I'll have to try this for my HT setup. My receiver supports a newer version of HDCP than my TV, and this confuses the content protection when playing from a web-browser. Right now I use a box that strips HDCP, but it gets very warm even when no source is plugged into it so I'm worried about its lifetime.

> And that’s the end of the story: the converters work, they’re passing through type 1 contents, and there’s nothing the movie studios can do about it. It’s all good.

Actually, they can... yank Lattice's license and/or keys for selling a chip that does things prohibited by the standard. That would render a ton of legitimate devices useless, but that also wasn't a problem when the HDCP v1 keys of a bunch of software BD/HDDVD players got yanked after their keys were dumped...

How would this work in practice if the device is never online and never updated with a list of acceptable device keys? Would it be applied at the encryption side to make keys that do not work with the offending key?

There is a provision that works using new content which could instruct the player to add certain keys to a revocation list. So if you buy a new Blu-ray and play it your player can be longer work with that key.

These systems are so thoroughly broken though that as far as I know this has never been used and the protection is more of a legal one.

again, it's the player that is blocking the key, which has been updated via a network connection that the user allowed to happen. If this is an inline device that is air gapped and doesn't even have a mechanism for updating the keys, how would this device ever be affected by its key being rejected?

Updates to the player can come with content. For streaming content, the provider can make streaming contingent on an updated firmware/application package that bans the hdcp keys. For disc based content, new discs can include key revocation.

That said, HDCP downgrading for compatibility is or at least was in the spec, so there's no justification to revoke the keys for the device discussed in the article.

right, but if you have a valid and current version of the player that decodes, say something like an app on an AppleTV 4K that pushes the video signal via HDMI, and inline box to bypass HDCP would not be affected by any key revocation what so ever. So again, how does this inline box get affected at all by any key revocation? After all, that's the subject of the TFA which we seem to have strayed a bit too far from the conversation with your hypothetical

What do you mean by ‘a player that decodes an app on an AppleTV’?

If your AppleTV is running an app that is playing media, that app is the player. And that app will add the new keys, that it finds in the media it is playing, to its revocation list so that app can no longer play any protected media to the blocked device. It will refuse to communicate with the inline box because the key used by the box is now on the revocation list.

And there probably is some mechanism that causes this to apply systemwide, either because the encryption and list management is in some dedicated chip or because the list is shared systemwide.

The inline box has to negotiate authentication with the player, which will see that the inline box has a revoked key and refuse to send data to it.

Thanks. This is the part that I was missing. So the Netflix/Prime/Hulu app receives the updated listed of revoked keys. When it sees that the device it is communicating with has a revoked key, it will refuse to play/launch/however it fails. At that point, it could even be put on Apple's shoulders that the AppleTV unit shouldn't even connect to that device and not be the app developers???

An app on Apple TV may be valid and current today, but if it's playing streaming media, it may not be valid and current to get streaming content tommorow. Updates to the app or Apple TV firmware could include revocations such that tomorrow's required version will not authenticate with your inline device.

The updates are included on ordinary movie discs.

I read the previous poster's comment as saying the revocation of the key would be embedded in newer content, and if the device is compliant it would revoke its own key when it encountered the newer content.

The device used in the original blog post is an Amazon streaming box, playing back video from Amazon's streaming service. So that device absolutely can be updated with new revocation lists.

For Blu-Ray players, discs contain updated revocation lists and players are required to store the most recent list. So any time you buy a new movie, you update that list. The delivery mechanism for this list is actually way more insidious than just having a file on the disc that players need to copy. There's actually a whole virtual machine in every Blu-Ray player, called BD+.

You see, if you were to just decrypt AACS[0] video data on a commercial Blu-Ray, you'd actually get a corrupted data stream, because you need to also run the BD+ program to get the fixup tables to unscramble the decrypted data. BD+ also adds facilities for the BD+ program to authenticate the player, inspect the state of the player software, and even run native code to update your player. If you don't provide the correct data[1] to the BD+ program, you don't get your fixup table, so every licensed Blu-Ray player implements BD+ such that all the inspection and update functionality works as intended.

[0] AACS is the DRM scheme that encrypts Blu-Ray disc data. It's HDCP's fraternal twin.

[1] Much of which is cryptographically signed and verifiable by the BD+ program

but the chip isn't doing anything prohibited by the standard. what they're doing is expressly allowed.

Can you then feed this into an HDCP 1 stripper?

Yep. There was an incident with this in 2015 when a Netflix movie was leaked in perfect 4K, horrifying movie studios. They found out that the pirate had used a HDCP 2.2 to 1.4 splitter; and immediately sued the manufacturer of the device.

They then quickly settled out of court when the manufacturer of the device showed in their own licensing manual that downgrading the HDCP version for compatibility wasn’t prohibited. Oops.

Yes, I believe this was referenced at the bottom of the article:

https://torrentfreak.com/4k-content-protection-stripper-beat...

For people who are wondering: $30 US, free domestic shipping. About the same price with different names on it at AliExpress.

> about the same price … at AliExpress.

It seems like this is something that Monoprice really excels at. Their markups on stuff like this is just remarkably low.

My biggest complaint about Monoprice is they've jacked up their prices over the past several years to switch over to the "free" shipping paradigm. Cables used to be less than a third of the current prices. Now they've tacked that one-unit shipping cost onto each unit even when you're buying more than one. I get that the market is heavily attracted towards lazily clicking "buy it now" on one or two things, but I really wish vendors would figure out a way of reconciling "free" shipping with the efficiency of batch ordering through significant quantity/order size discounts and whatnot. Maybe Monoprice will eventually get there with their business account type, but I haven't seen signs of that yet.

As for the original article, cool protocol dissection. But I can't fathom needing to care about HDCP versions. If your video source makes you deal with hostile anti-features, get a new video source.

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